Steina Alexandra, Sure Sarah, Butz Markus, Vesper Jan, Schnitzler Alfons, Hirschmann Jan
Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany.
Department of Functional Neurosurgery and Stereotaxy, Neurosurgical Clinic, Medical Faculty, Heinrich Heine University, 40225 Düsseldorf, Germany.
Neuroimage Clin. 2025 Jul 17;48:103848. doi: 10.1016/j.nicl.2025.103848.
The ventral intermediate nucleus of the thalamus (VIM) is the main thalamic hub for cerebellar inputs and the primary deep brain stimulation target in essential tremor (ET). As such, it presumably plays a critical role in motor control. However, this structure is rarely studied in humans, and existing studies mostly focus on tremor. Here, we studied neural oscillations in the VIM and their coupling to cortical oscillations during voluntary movement. We investigated thalamo-cortical coupling, combining recordings of thalamic local field potentials and magnetoencephalography, in 10 ET patients with externalized deep brain stimulation electrodes. During the recording, patients repeatedly pressed a button in response to a visual cue. In a whole-brain analysis of VIM-cortex coherence, we contrasted activity during pre-movement baseline and button pressing. Button pressing was associated with a bilateral decrease of thalamic alpha (8-12 Hz) and beta (13-21 Hz) power and a contralateral gamma (35-90 Hz) power increase. Alpha/low-beta (8-20 Hz) coherence decreased during movement. This effect localized to the supplementary motor area and premotor cortex. A high-beta (21-35 Hz) coherence increase occurred in the same region but was more focal than the suppression. Pre-movement levels of thalamo-cortex low-beta coherence correlated with reaction time. Our results demonstrate that voluntary movement is associated with modulations of behaviourally relevant thalamic coupling, primarily to premotor areas. We observed a clear distinction between low- and high-beta frequencies and our results suggest that the concept of "antikinetic" beta oscillations, originating from research on Parkinson's disease, is transferable to ET.
丘脑腹中间核（VIM）是小脑输入的主要丘脑枢纽，也是特发性震颤（ET）中主要的脑深部刺激靶点。因此，它可能在运动控制中起着关键作用。然而，该结构在人类中很少被研究，现有研究大多集中在震颤方面。在此，我们研究了VIM中的神经振荡及其在自主运动过程中与皮层振荡的耦合。我们结合丘脑局部场电位记录和脑磁图，对10例植入外置脑深部刺激电极的ET患者进行了丘脑 - 皮层耦合研究。在记录过程中，患者根据视觉提示反复按下按钮。在对VIM - 皮层相干性的全脑分析中，我们对比了运动前基线期和按钮按压期间的活动情况。按钮按压与丘脑α波（8 - 12Hz）和β波（13 - 21Hz）功率的双侧降低以及对侧γ波（35 - 90Hz）功率的增加有关。运动期间α/低β波（8 - 20Hz）相干性降低。这种效应定位于辅助运动区和运动前皮层。同一区域出现高β波（21 - 35Hz）相干性增加，但比抑制现象更局限。运动前丘脑 - 皮层低β波相干性水平与反应时间相关。我们的结果表明，自主运动与行为相关的丘脑耦合调制有关，主要是与运动前区的耦合。我们观察到低β波和高β波频率之间有明显区别，并且我们的结果表明，源自帕金森病研究的“抗运动”β振荡概念可应用于ET。
